%clc;clear;
% syms u v a
% eqns = [a*u + v == 0, u - v == 1];
% S = solve(eqns, [u v])
% S.u
% S.v

% syms l0 l1 l2 a2 theta2 theta23;
% eqns = [l0 == a2*cos(theta2)+l2*sin(theta23), l1 == a2*sin(theta2)-l2*cos(theta23)];
% S = solve(eqns, [theta2 theta23]);
% simplify(S.theta2)
% simplify(S.theta23)

syms c5 r11 r21 theta4 theta6;
eqns = [r11 == cos(theta4)*cos(theta6) - sin(theta4)*sin(theta6), r21 == sin(theta4)*cos(theta6) + cos(theta4)*sin(theta6)];
S = solve(eqns, [theta4 theta6]);
simplify(S.theta4)
simplify(S.theta6)
